Remove use of pthread_cancel in asnyc threaded resolving. While there
are system where this works, others might leak to resource leakage
(memory, files, etc.). The popular nsswitch is one example where resolve
code can be dragged in that is not prepared.
The overall promise and mechanism of pthread_cancel() is just too
brittle and the historcal design of getaddrinfo() continues to haunt us.
Fixes#18532
Reported-by: Javier Blazquez
Closes#18540
Add optional detail to `Curl_resolver_error()` to add to failure message
where available. This makes, for c-ares, the reason for a failed
resource available to the user without extra trace config.
When "dns" tracing enabled, print the c-ares server config at the start
of a resolve.
Closes#18251
Changed strategy to start up and terminate resolver thread.
When starting up:
Start the thread with mutex acquired, wait for signal from thread that
it started and has incremented the ref counter. Thread set
pthread_cancel() to disabled before that and only enables cancelling
during resolving itself. This assure that the ref counter is correct and
the unlinking of the resolve context always happens.
When shutting down resolving:
If ref counting shows thread has finished, join it, free everything. If
thread has not finished, try pthread_cancel() (non Windows), but keep
the thread handle around.
When destroying resolving:
Shutdown first, then, if the thread is still there and 'quick_exit' is
not set, join it and free everything. This might occur a delay if
getaddrinfo() hangs and cannot be interrupted by pthread_cancel().
Destroying resolving happens when another resolve is started on an
easy handle or when the easy handle is closed.
Add test795 to check that connect timeout triggers correctly
when resolving is delayed. Add debug env var `CURL_DNS_DELAY_MS`
to simulate delays in resolving.
Fix test1557 to set `quick_exit` and use `xxx.invalid` as domain
instead of `nothing` that was leading to hangers in CI.
Closes#18263
* Add more tracing information to c-ares errors.
* remove CURL_ASYNC_SUCCESS, rename `ares->last_status` to
`ares->ares_status`. Give trace explanation for "common"
errors
* add ares "csv" information to tracing on failure
* DoH: invoke `Curl_resolver_error()` on failure to populate
error buf
Closes#18247
`getsock()` calls operated on a global limit that could
not be configure beyond 16 sockets. This is no longer adequate
with the new happy eyeballing strategy.
Instead, do the following:
- make `struct easy_pollset` dynamic. Starting with
a minimal room for two sockets, the very common case,
allow it to grow on demand.
- replace all protocol handler getsock() calls with pollsets
and a CURLcode to return failures
- add CURLcode return for all connection filter `adjust_pollset()`
callbacks, since they too can now fail.
- use appropriately in multi.c and multi_ev.c
- fix unit2600 to trigger pollset growth
Closes#18164
Instead of using integer seconds. Also: if the cache contains over
30,000 entries after first pruning, it makes anoter round and removes
all entries that are older than half the age of the oldest entry until
it goes below 30,000.
Closes#18160
New multi option CURLMOPT_NETWORK_CHANGED with a long bitmask value:
- CURLM_NWCOPT_CLEAR_CONNS: do not reuse existing connections, close all
idle connections.
- CURLM_NWCOPT_CLEAR_DNS: clear the multi's DNS cache.
All other bits reserved for future extensions.
Fixes#17225
Reported-by: ウさん
Closes#17613
The `struct Curl_dns_entry *` used to established a connection
do not have the connection's lifetime, but the transfer's lifetime
(of the transfer that initiates the connect).
`Curl_dns_entry *` is reference counted with the "dns cache". That
cache might be owned by the multi or the transfer's share. In the
share, the reference count needs updating under lock.
Therefore, the dns entry can only be kept *and* released using the
same transfer it was initially looked up from. But a connection is
often discarded using another transfer.
So far, the problem of this has been avoided in clearing the connection's
dns entries in the "multi_don()" handling. So, connections had NULL
dns entries after the initial transfers and its connect had been handled.
Keeping the dns entries in data->state seems therefore a better choice.
Also: remove the `struct Curl_dns_entry *` from the connect filters
contexts. Use `data->state.dns` every time instead and fail correctly
when not present and needed.
Closes#17383
Move curlx_ functions into its own subdir.
The idea is to use the curlx_ prefix proper on these functions, and use
these same function names both in tool, lib and test suite source code.
Stop the previous special #define setup for curlx_ names.
The printf defines are now done for the library alone. Tests no longer
use the printf defines. The tool code sets its own defines. The printf
functions are not curlx, they are publicly available.
The strcase defines are not curlx_ functions and should not be used by
tool or server code.
dynbuf, warnless, base64, strparse, timeval, timediff are now proper
curlx functions.
When libcurl is built statically, the functions from the library can be
used as-is. The key is then that the functions must work as-is, without
having to be recompiled for use in tool/tests. This avoids symbol
collisions - when libcurl is built statically, we use those functions
directly when building the tool/tests. When libcurl is shared, we
build/link them separately for the tool/tests.
Assisted-by: Jay Satiro
Closes#17253
"asyn" is the internal name under which both c-ares and threaded
resolver operate. Make the naming more consistent. Implement the c-ares
resolver in `asyn-ares.*` and the threaded resolver in `asyn-thrdd.*`.
The common functions are in `asyn-base.c`.
When `CURLRES_ASYNCH` is defined, either of the two is used and
`data->state.async` exists. Members of that struct vary for the selected
implementation, but have the fields `hostname`, `port` and `ip_version`
always present. This are populated when the async resolving starts and
eliminate the need to pass them again when checking on the status and
processing the results of the resolving.
Add a `Curl_resolv_blocking()` to `hostip.h` that relieves FTP and SOCKS
from having to repeat the same code.
`Curl_resolv_check()` remains the function to check for status of
ongoing resolving. Now it also performs internally the check if the
needed DNS entry exists in the dnscache and if so, aborts the asnyc
operation. (libcurl right now does not check for duplicate resolve
attempts. an area for future improvements).
The number of functions in `asyn.h` has been reduced. There were subtle
difference in "cancel()" and "kill()" calls, both replaced by
`Curl_async_shutdown()` now. This changes behaviour for threaded
resolver insofar as the resolving thread is now always joined unless
`data->set.quick_exit` is set. Before this was only done on some code
paths. A future improvement would be a thread pool that keeps a limit
and also could handle joins more gracefully.
DoH, not previously tagged under "asny", has its struct `doh_probes` now
also in `data->state.async`, moved there from `data->req` because it
makes more sense. Further integration of DoH underneath the "asyn"
umbrella seems like a good idea.
Closes#16963
Slight refactoring around dnscache, e.g. hostcache
- eliminate `data->state.hostcache`. Always look up
relevant dnscache at share/multi.
- unify naming to "dnscache", replacing "hostcache"
- use `struct Curl_dnscache`, even though it just
contains a `Curl_hash` for now.
- add `Curl_dnscache_destroy()` for cleanup in
share/multi.
Closes#16941
Allow building with c-ares and yet use threaded resolver for the main
host A/AAAA resolving:
`--with-ares` provides the c-ares install path and defaults to use
c-ares for name resolving
`--with-threaded-resolver` still uses c-ares in the build (for HTTPS)
but uses the threaded resolver for "normal" resolves.
It works similarly for cmake: ENABLE_ARES enables ares, and if
ENABLE_THREADED_RESOLVER also is set, c-ares is used for HTTPS RR and
the threaded resolver for "normal" resolves.
HTTPSRR and c-ares-rr are new features return by curl_version_info() and
thus shown by curl -V.
The c-ares-rr feature bit is there to make it possible to distinguish
between builds using c-ares for all name resolves and builds that use
the threaded resolves for the regular name resolves and c-ares for
HTTPSRR only. "c-ares-rr" means it does not use c-ares for "plain" name
resolves.
HTTPSRR support is EXPERIMENTAL only.
Closes#16054
When enabled in the build.
Update test2100: verify with HTTPS RR included
Adjust runtests and server/disabled.c to include "HTTPSRR" as a feature
in the test suite.
Also, decode the ALPN list in HTTPS records straight into IDs. There's
no point in storing everything in string format. Skip ALPNs we do not
support.
Closes#16007
Use these words and casing more consistently across text, comments and
one curl tool output:
AIX, ALPN, ANSI, BSD, Cygwin, Darwin, FreeBSD, GitHub, HP-UX, Linux,
macOS, MS-DOS, MSYS, MinGW, NTLM, POSIX, Solaris, UNIX, Unix, Unicode,
WINE, WebDAV, Win32, winbind, WinIDN, Windows, Windows CE, Winsock.
Mostly OS names and a few more.
Also a couple of other minor text fixups.
Closes#14360
Replace Curl_resolv_unlock() with Curl_resolv_unlink():
-replace inuse member with refcount in Curl_dns_entry
- pass Curl_dns_entry ** to unlink, so it gets always cleared
- solve potential (but unlikley) UAF in FTP's handling of looked up
Curl_dns_entry. Esp. do not use addr information after unlinking an entry.
In reality, the unlink will not free memory, as the dns entry is still
referenced by the hostcache. But this is not safe and relying on no other
code pruning the cache in the meantime.
- pass permanent flag when adding a dns entry instead of fixing timestamp
afterwards.
url.c: fold several static *resolve_* functions into one.
Closes#14195
Based on the standards and guidelines we use for our documentation.
- expand contractions (they're => they are etc)
- host name = > hostname
- file name => filename
- user name = username
- man page => manpage
- run-time => runtime
- set-up => setup
- back-end => backend
- a HTTP => an HTTP
- Two spaces after a period => one space after period
Closes#14073
Before this patch, two macros were used to guard IPv6 features in curl
sources: `ENABLE_IPV6` and `USE_IPV6`. This patch makes the source use
the latter for consistency with other similar switches.
`-DENABLE_IPV6` remains accepted for compatibility as a synonym for
`-DUSE_IPV6`, when passed to the compiler.
`ENABLE_IPV6` also remains the name of the CMake and `Makefile.vc`
options to control this feature.
Closes#13349
Delete checks and guards for standard C89 headers and assume these are
available: `stdio.h`, `string.h`, `time.h`, `setjmp.h`, `stdlib.h`,
`stddef.h`, `signal.h`.
Some of these we already used unconditionally, some others we only used
for feature checks.
Follow-up to 9c7165e96a#11918 (for `stdio.h` in CMake)
Closes#11940
- they are mostly pointless in all major jurisdictions
- many big corporations and projects already don't use them
- saves us from pointless churn
- git keeps history for us
- the year range is kept in COPYING
checksrc is updated to allow non-year using copyright statements
Closes#10205
Commit 3b16575ae9 removed support for
building on Novell Netware, but a few leftover traces remained. This
removes the last bits.
Closes: #9966
Reviewed-by: Daniel Stenberg <daniel@haxx.se>
Have curl_multi_init() use a much larger DNS hash table than used for
the easy interface to scale and perform better when used with _many_
host names.
curl_share_init() sets an in-between size.
Inspired-by: Ivan Tsybulin
See #9340Closes#9376
Add licensing and copyright information for all files in this repository. This
either happens in the file itself as a comment header or in the file
`.reuse/dep5`.
This commit also adds a Github workflow to check pull requests and adapts
copyright.pl to the changes.
Closes#8869
- Do not assume IPv6 is not working when getaddrinfo is not present.
The check to see if IPv6 actually works is now independent of whether
there is any resolver that can potentially resolve a hostname to IPv6.
Prior to this change if getaddrinfo() was not found at compile time then
Curl_ipv6works() would be defined as a macro that returns FALSE.
When getaddrinfo is not found then libcurl is built with CURLRES_IPV4
defined instead of CURLRES_IPV6, meaning that it cannot do IPv6 lookups
in the traditional way. With this commit if libcurl is built with IPv6
support (ENABLE_IPV6) but without getaddrinfo (CURLRES_IPV6), and the
IPv6 stack is actually working, then it is possible for libcurl to
resolve IPv6 addresses by using DoH.
Ref: https://github.com/curl/curl/issues/7483#issuecomment-890765378
Closes https://github.com/curl/curl/pull/7529
Also, use a single function library-wide for detecting if a given hostname is
a numerical IP address.
Reported-by: Harry Sintonen
Fixes#7146Closes#7149
... with the help of Curl_resolver_error() which now is moved from
asyn-thead.c and is provided globally for this purpose.
Follow-up to 35ca04ce1b
Makes test 1188 work for c-ares builds
Closes#6626
... in most cases instead of 'struct connectdata *' but in some cases in
addition to.
- We mostly operate on transfers and not connections.
- We need the transfer handle to log, store data and more. Everything in
libcurl is driven by a transfer (the CURL * in the public API).
- This work clarifies and separates the transfers from the connections
better.
- We should avoid "conn->data". Since individual connections can be used
by many transfers when multiplexing, making sure that conn->data
points to the current and correct transfer at all times is difficult
and has been notoriously error-prone over the years. The goal is to
ultimately remove the conn->data pointer for this reason.
Closes#6425
Extend the syntax of CURLOPT_RESOLVE strings: allow using a '+' prefix
(similar to the existing '-' prefix for removing entries) to add
DNS cache entries that will time out just like entries that are added
by libcurl itself.
Append " (non-permanent)" to info log message in case a non-permanent
entry is added.
Adjust relevant comments to reflect the new behavior.
Adjust documentation.
Extend unit1607 to test the new functionality.
Closes#6294
- Stick to a single unified way to use structs
- Make checksrc complain on 'typedef struct {'
- Allow them in tests, public headers and examples
- Let MD4_CTX, MD5_CTX, and SHA256_CTX typedefs remain as they actually
typedef different types/structs depending on build conditions.
Closes#5338
Previously it was stored in a global state which contributed to
curl_global_init's thread unsafety. This boolean is now instead figured
out in curl_multi_init() and stored in the multi handle. Less effective,
but thread safe.
Closes#4851
It was used (intended) to pass in the size of the 'socks' array that is
also passed to these functions, but was rarely actually checked/used and
the array is defined to a fixed size of MAX_SOCKSPEREASYHANDLE entries
that should be used instead.
Closes#4169
There were a leftover few prototypes of Curl_ functions that we used to
export but no longer do, this removes those prototypes and cleans up any
comments still referring to them.
Curl_write32_le(), Curl_strcpy_url(), Curl_strlen_url(), Curl_up_free()
Curl_concat_url(), Curl_detach_connnection(), Curl_http_setup_conn()
were made static in 05b100aee2.
Curl_http_perhapsrewind() made static in 574aecee20.
For the remainder, I didn't trawl the Git logs hard enough to capture
their exact time of deletion, but they were all gone: Curl_splayprint(),
Curl_http2_send_request(), Curl_global_host_cache_dtor(),
Curl_scan_cache_used(), Curl_hostcache_destroy(), Curl_second_connect(),
Curl_http_auth_stage() and Curl_close_connections().
Closes#4096
Reviewed-by: Daniel Stenberg <daniel@haxx.se>
Due to limitations in Curl_resolver_wait_resolv(), it doesn't work for
DOH resolves. This fix disables DOH for those.
Limitation added to KNOWN_BUGS.
Fixes#3850Closes#3857
